Pregnancy monitoring system and method

ABSTRACT

The present invention relates to a pregnancy monitoring system, the system comprising a fetal monitoring transducer ( 20 ) arranged to detect fetal medical condition information; and a control device ( 48 ) comprising a motion assessment unit ( 50 ) and a signal output unit ( 52 ); wherein the fetal monitoring transducer ( 20 ) is arranged to detect fetal movement indicative information, wherein the motion assessment unit ( 50 ) is arranged to process fetal movement grading information, in addition to the fetal movement indicative information, wherein the signal output unit ( 52 ) is arranged to simultaneously output a fetal condition signal, particularly a fetal heart rate signal, and an augmented fetal movement signal based on the fetal movement indicative information and the fetal movement grading information, wherein a characteristic property of the original fetal movement information is still present in the augmented fetal movement signal. The disclosure further relates to a corresponding pregnancy monitoring method.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of co-pending U.S. patentapplication Ser. No. 16/082,699, filed Sep. 6, 2018, which is the U.S.National Phase application under 35 U.S.C. § 371 of InternationalApplication No. PCT/EP2017/057698 filed Mar. 31, 2017 2011, which claimsthe benefit of International Application No. EP16163121.3 filed Mar. 31,2016. These applications are hereby incorporated by reference herein.

FIELD OF THE INVENTION

The present disclosure relates to a pregnancy monitoring system and to apregnancy monitoring method for detecting medical condition informationfrom a pregnant subject of interest. More particularly, but not intendedto limit the scope of the invention, the present disclosure relates toimprovements in cardiotocography devices and methods used for monitoringa fetus in a pregnant woman.

The present invention further relates to a corresponding computerprogram.

BACKGROUND OF THE INVENTION

US 2016/0058363 A1 discloses a method of monitoring fetal movement,comprising obtaining a signal comprising a first record of fetalmovements from a first sensor device applied to a mother's abdomen,obtaining a second record of perceived fetal movements manually input bya user for a time period concurrent with the first record of fetalmovement, comparing the first and second records, and providing a log offetal movements over time based upon said comparison.

Pregnancy monitoring which may be also referred to as fetal monitoringand/or labor monitoring is commonly used in late stages of pregnancy. Byway of example, during labor, physiological parameters such as fetalheart rate may be monitored so as to identify signs of fetal distressand/or fetal well-being. Prior to labor, the mother-to-be may undergoone or more medical ultrasound examinations, thereby providing fetalheart rate information, fetal movement information, fetal sizeinformation and similar information that is used to identify markers offetal growth during pregnancy. During labor and birth, also uterineactivity, particularly uterine contractions, may be monitored.

In gynecology and obstetrics, generally two medical parameters areimportant to assess the condition of the fetus. These two parameters arethe fetal beat-to-beat heart rate, e.g. measured via an ultrasoundDoppler signal, and uterus (or labor) activity. Simultaneous assessmentof the fetal heart rate (FHR) and uterine activity allows an exactdetermination of the fetal condition. Monitoring systems that arecapable of detecting both parameters are frequently referred to ascardiotocographs (CTG monitors). However, also fetal movement isconsidered as an indicative parameter for assessing the condition of thefetus.

By way of example, a conventional CTG device (cardiotocography device)may contain an ultrasound Doppler transducer (US transducer) formeasuring fetal heart rate (FHR) and detecting fetal movements, as wellas a pressure transducer (also called toco transducer, ortocodynamometer) for measuring uterine activity. Each of the transducersmay be placed on the abdomen of the mother, e.g. by an elastic beltfitted around the waist or by an adhesive tape or patch. Each of thetransducers may be mounted inside a respective probe. Particularly theultrasound transducer may be manually placed and positioned so as toseek for a considerably strong signal, e.g. a considerably strong heartbeat or heart rate signal. An ideal position of the ultrasoundtransducer at the expectant mother's abdomen may depend on an actualorientation of the fetus.

It has been observed that motion of the fetal movement transducers,e.g., due to (re)positioning of the transducer and/or due to maternalmovement may cause the ultrasound transducer to falsely indicate fetalmovement. As a result, fetal movement detections are usually onlyreliable when there are no motion artifacts.

WO 2015/062851 A1 discloses a pregnancy monitoring system and method,the system comprising a fetal monitoring transducer that detects fetalmedical condition information; a first motion sensor unit associatedwith the fetal monitoring transducer, the first motion sensor unitcomprising at least one first motion sensor; a second motion sensor unitcomprising at least one second motion sensor; and a control devicecomprising an evaluation unit that determines relative motion betweenthe first motion sensor unit and the second motion sensor unit, whereinthe determination of relative motion is based on motion signals suppliedby the at least one first motion sensor and the at least one secondmotion sensor. At least one of the at least one first motion sensor andthe at least one second motion sensor is attachable to an abdominalregion of a subject of interest.

The control device selectively permits, in an enablement mode,processing of the detected fetal medical condition information when alevel of relative motion between the first motion sensor unit and thesecond motion sensor unit indicates stable measurement conditions.Further, the control device selectively prevents, in a suppression mode,processing of the detected fetal medical condition information when thelevel of relative motion between the first motion sensor unit and thesecond motion sensor unit indicates unstable measurement conditions.

A means of displaying CTG information involves so-called CTG tracesincluding simultaneous mid-term or long-term charts of, for instance, afetal heart rate signal, a uterine activity signal, an a fetal movementsignal. The CTG traces may be printed on paper (involving thermalprinting on thermal paper, for instance), or may be digitally stored anddisplayed on a (computer) monitor in an instant or delayed fashion. Atypical plot or printout of the CTG signal signals involves two or threetraces using the same time base. The traces are typically spaced fromone another, e.g. on top of one another, in the CTG plot.

Common CTG monitoring systems, for instance, detect fetal movements as aside product from the Doppler signal based on which the fetal heart ratesignal is obtained. Fetal movements may be rather complex, particularlyin terms of their impact on the Doppler signal. Fetal movements mayinvolve head movements, limb movements, but also turning and tossing ofthe fetal body. Further, minor specific movements, such as fetalsucking, may manifest themselves in the Doppler signal.

Therefore, common CTG monitoring systems process a potential fetalmotion signal that is present in the Doppler signal and provide abasically binary output signal which may involve, for instance,so-called fetal movement blocks affirming that, in accordance with theapplied algorithm, fetal movements are found to be present at theparticular time instance. Hence, a binary fetal movement indication isprovided.

As discussed in WO 2015/062851 A1, further non-indicative movements maycause a distortion of the fetal motion signal or even cause incorrectfetal movements indications. Non-indicative movements may involvematernal movements, displacements of the involved sensors ortransducers, and movements due to the fetus' inertia level, i.e. whenthe fetus is moved in a delayed fashion in response to maternalmovements, particularly maternal posture changes.

As a result, also the binary fetal movement indication may be afflictedwith false indications.

Nevertheless, it has been observed that clinical staff includingdoctors, obstetricians, nurses and midwifes became familiar with thefetal movement blocks as a fundamental component of the CTG plots. Eventhough it is known in theory that sometimes the fetal movementindications are caused by non-fetal movement occurrences, the clinicalstaff appreciates the supplemental information in the CTG plot providedby the fetal movement blocks.

SUMMARY OF THE INVENTION

It is an object of the present disclosure to provide for a pregnancymonitoring system and a related method that may allow for an improvedmonitoring accuracy and reliability. It would be further advantageous toprovide for a system and a method that are less susceptible tomotion-related mismeasurements. Preferably, the system and method aresuitably arranged for enabling reliable measurements also under externalmotion-afflicted monitoring conditions. It would be further advantageousto provide for a system and a method that are widely accepted by theoperating medical staff and that do not pose major adaptive challenges.Preferably, the system can be operated with little on even no adaptionor readjustment of the clinical practice, assuming that the medicalstaff is used to a certain type of common pregnancy monitoring systems.

In accordance with a first aspect of the present disclosure, acardiotocographic pregnancy monitoring system is presented, the systemcomprising:

-   -   a fetal monitoring transducer arranged to detect fetal medical        condition information and comprising at least one ultrasound        sensor;    -   a control device comprising a motion assessment unit and a        signal output unit;    -   a maternal monitoring transducer comprising at least one        tocodynamometer transducer; and        -   a motion evaluation unit comprising at least one motion            verification transducer;    -   wherein the fetal monitoring transducer is arranged to detect        fetal movement indicative information,    -   wherein the motion assessment unit is arranged to process fetal        movement grading information, in addition to the fetal movement        indicative information,    -   wherein the maternal monitoring transducer is arranged to detect        maternal medical condition information,    -   wherein the motion assessment unit processes the fetal movement        grading information based on a motion verification signal        provided by the motion evaluation unit, and    -   wherein the signal output unit is arranged to simultaneously        output        -   a fetal condition signal, particularly a fetal heart rate            signal,        -   a maternal condition signal, particularly a uterine activity            signal, and        -   an augmented fetal movement signal based on the fetal            movement indicative information and the fetal movement            grading information, wherein a characteristic property of            the original fetal movement information is still present in            the augmented fetal movement signal.

This aspect is based on the insight that the medical staffs acceptanceis crucial for implementing refined monitoring systems and/or method. Ithas been observed that the potentially afflicted fetal movement blocksin the CTG charts are widely accepted, even though the fetal movementinformation is sometimes corrupted.

In the above WO 2015/062851 A1, it is suggested to prevent the fetalmovement signal is case of detected distortions that are notattributable to genuine fetal movements of interest. Hence, when thefetal movement indication in the CTG plot is prevented, e.g. due tomassive maternal motion and/or further distorting artifacts, the medicalstaff that is used to the presence of the fetal movement blocks (whethercorrect indications or wrong ones) would readily conclude that no fetalmotion is present which might be indicative of an emergency situation.

As an example, when an expectant mother undergoes a CTG monitoringsession at the beginning of the labor stage, no immediate, permanenton-site presence of a nurse or midwife is necessary. Rather, typicallysome remote supervision of the CTG monitoring session will performed,e.g. from a remote nurse's room. When the expectant mother decides towalk around and/or the change her posture, it may not be unlikely that afetal movement indication would be induced, due to the external motioninvolved. Fetal movements' presence is what a remote supervising nursequite likely would conclude.

If the respective signal was suppressed, as described in WO 2015/062851A1, the supervising nurse might feel uncomfortable and draw falseconclusions, assuming that for a considerably long term no fetalmovement indication is present. This might adversely affect thedissemination and acceptance of improved pregnancy monitoring systems.

Therefore, it is proposed to maintain the well-accepted layout of theCTG plot and to augment or enrich the fetal movement indications.However, this involves, as a general constraint, that excess informationshould be prevented which might cause uncertainty. It is thereforeproposed to indicate an actual fetal movement validity indicating signalin or next to the rather simple fetal movement indications.

Hence, the medical staff still can promptly grasp a current fetalmovement state which, however, now also involves reliabilityinformation. Assuming that it is indicated that the fetal movementsignal is corrupted/distorted by maternal movements, for instance,though apparently a clear fetal movement indication is present,corrective action may take place. For instance, the expectant mother maybe prompted to assume a more appropriate posture and/or to stop walkingaround.

Generally, the fetal movement grading information may be representativeof unstable measurement conditions. The fetal condition signal and theaugmented fetal movement signal may be displayed and/or printed insynchronism in the same CTG plot having the same time scale.

The motion assessment unit that processes the fetal movement gradinginformation, in addition to the fetal movement indicative information,may operate in accordance with the teaching of WO 2015/062851 A1. Thatis, in addition to the US transducer further motions sensor unitsimplementing motions sensors may be provided. Further, relative motionbetween a first motion sensor unit and a second motion sensor unit maybe detected, wherein a determination of relative motion is based onmotion signals supplied by at least one first motion sensor and at leastone second motion sensor.

One of the sensors may be associated with or attached to the fetalmonitoring transducer, e.g. the US transducer. The other sensor may beassociated with or attached to the maternal monitoring transducer. Moregenerally, the other sensor may be attached to an abdominal portion ofthe expectant mother, spaced away from the fetal monitoring transducer.Relative motion between the first sensor and the second sensor mayindicate non-fetal movement which, however, might be reflected in thecomputed fetal movement indicative information. It is thereforebeneficial to provide fetal movement grading information to make theoperator aware of the distortions.

However, in at least some embodiments, not separate motion sensors forexternal (non-fetal) motion are required. Rather, already presentsignals may be used to assess a reliability degree of the fetal movementindications. For instance, the data obtained by the US transducer may beprocessed so as to assess the fetal movement indication reliability.Hence, by applying adopted evaluation algorithms, movement indicationquality state information may be obtained.

For instance, several characteristic patterns in the received ultrasoundDoppler signal may be indicative of non-fetal movements, or even ofnon-indicative small-scale fetal movements. Hence, also the alreadyavailable signals may be used to detect the fetal movement gradinginformation. Meanwhile, obstetric ultrasound technology has been furtherdeveloped and improved to a level that enables more detailedexaminations and evaluations.

In an exemplary embodiment, the system further comprises a maternalmonitoring transducer arranged to detect maternal medical conditioninformation, particularly uterine activity indicative information,wherein the signal output unit is arranged to simultaneously output

-   -   the fetal condition signal,    -   a maternal condition signal, particularly a uterine activity        signal, and    -   the augmented fetal movement signal.

Hence, the fetal condition signal, the uterine activity signal and theaugmented fetal movement signal may be displayed and/or printed insynchronism in the same CTG plot having the same time scale.

In another exemplary embodiment of the system, the augmented fetalmovement signal involves a base portion including a binary signalindicating the presence of fetal movement at least substantially basedon the fetal movement indicative information detected by the fetalmonitoring transducer, and an augmentation portion indicating a signalquality level of the base portion. The signal quality level may bereferred to as signal reliability level.

The base portion may be solely or exclusively based on the fetalmovement indicative information detected by the fetal monitoringtransducer. Hence, in this exemplary embodiment, the fetal movementindicative information basically corresponds to the signal which isdisplayed in common CTG systems that provide fetal movement blocks.

In an exemplary refinement, the augmented fetal movement signal is aternary signal or a tertiary signal arranged to assume three states inincluding a movement state, a non-movement state, and a potentiallydistorted signal state, and wherein the motion assessment unitdetermines at least the potentially distorted signal state.

Hence, the medical staff can readily grasp and understand the presentedinformation. The informative content is greatly enriched, but stillclear and manageable.

In another exemplary embodiment of the system, the signal output unit isarranged to provide a simultaneous visual reading of the fetal conditionsignal, the uterine activity signal, and the augmented fetal movementsignal, wherein the augmented fetal movement signal involves a blockrepresentation of the presence of fetal movements and a grading signalbased on the grading information.

Several options of how to present a clear visual reading within theconstraints of CTG devices and typical plots may be envisaged.

In an exemplary refinement, the grading signal is an embedded gradingsignal and includes at least one of a color change of the blockrepresentation, a pattern variation of the block representation, a shapechange of the block representation, and a magnitude change of the blockrepresentation.

In another exemplary refinement, the grading signal includes a paralleltrace presented in the vicinity of the block representation and insynchronism therewith.

In another exemplary refinement, the grading signal is one of a binarysignal, preferably a block signal, and a multi-level signal arranged toassume a number of states that is greater than 2. However, also amulti-level signal is to be understood as a discrete signal which mayassume a limited number of discrete states. Hence, no analog orquasi-analog chart shall be provided.

In another exemplary embodiment, the system further comprises a motionevaluation unit comprising at least one motion verification transducer,wherein the motion assessment unit processes the fetal movement gradinginformation based on a motion verification signal provided by the motionevaluation unit.

In this context, reference is made to the above discussed WO 2015/062851A1. Instead of suppressing a potentially distorted fetal movementsignal, it is proposed to provide an augmented signal in accordance withthe present disclosure so as to meet the medical staffs expectations andhabits.

In an exemplary refinement, the motion evaluation unit comprises a firstmotion verification transducer and a second motion verificationtransducer, wherein the motion assessment unit is arranged to determinerelative motion between the first motion verification transducer and thesecond motion verification transducer, wherein the fetal movementgrading information is dependent on an actual level of relative motion.

In another exemplary refinement, the first motion verificationtransducer is associated with the fetal monitoring transducer, andwherein the second motion verification transducer is arranged to beattached to an abdominal region at a distance from the first motionverification transducer and preferably associated with the maternalmonitoring transducer.

In another exemplary embodiment of the system, the first motionverification transducer is associated with the fetal monitoringtransducer and the second motion verification transducer is associatedwith the maternal monitoring transducer.

In another exemplary embodiment of the system, the first motionverification transducer and the second motion verification transducerare arranged as motion sensor units involving motion sensors, andwherein the motion evaluation unit detects relative motion between afirst motion sensor unit and a second motion sensor unit based on motionsignals supplied by at least one first motion sensor of the first motionsensor unit and at least one second motion sensor of the second motionsensor unit

In another exemplary embodiment of the system, the fetal movementgrading information is further indicative of a type of movementdistortion, including at least one of maternal activity, transducershifting, delayed inertia fetal movement, and characteristic small scalefetal activities.

In another exemplary embodiment of the system, the fetal movementgrading information is further indicative of a type of indicative fetalmovements, including at least one of limb movements involving armmovements and leg movements, torso movements, and head movements.Further, the type of indicative fetal movements may also include thepresence of kicks, rolls, etc.

For instance, the fetal movement grading information may be displayed orprinted my means of symbols adjacent to the original fetal movementblocks. The symbols represent respective movement assessment qualitystates or respective types of movements.

In accordance with another aspect of the present disclosure, acardiotocographic pregnancy monitoring method is presented, the methodcomprising the steps of:

-   -   providing a fetal monitoring transducer and detecting fetal        medical condition information involving detecting fetal movement        indicative information, based on ultrasound monitoring;    -   providing a maternal monitoring transducer and detecting        maternal medical condition information, based on tocodynamometer        monitoring; and    -   controlling the monitoring process involving motion assessment        and output signal generation;    -   wherein the motion assessment involves processing fetal movement        grading information, in addition to the fetal movement        indicative information, based on a motion verification signal        obtained from a motion evaluation unit,    -   wherein the output signal generation involves simultaneously        providing:        -   a fetal condition signal, particularly a fetal heart rate            signal, obtained from the fetal monitoring transducer,        -   a maternal condition signal, particularly a uterine activity            signal, obtained from the maternal monitoring transducer,            and        -   an augmented fetal movement signal based on the fetal            movement indicative information and the fetal movement            grading information, wherein a characteristic property of            the original fetal movement information is still present in            the augmented fetal movement signal.

In an exemplary embodiment of the method, the motion verification signalis indicative of an actual level of relative motion between a firstmotion verification transducer and a second motion verificationtransducer of the motion evaluation unit.

In an exemplary embodiment, the method further comprises the step ofproviding a maternal monitoring transducer arranged to detect maternalmedical condition information, particularly uterine activity indicativeinformation, wherein the output signal generation involvessimultaneously providing:

-   -   the fetal condition signal,    -   a uterine activity signal, and    -   the augmented fetal movement signal.

In another exemplary embodiment of the method, the augmented fetalmovement signal involves a base portion including a binary signalindication the presence of fetal movement solely based on the fetalmovement indicative information detected by the fetal monitoringtransducer, and an augmentation portion indicating a signal qualitylevel of the base portion.

In yet another aspect of the present invention, there is provided acomputer program which comprises program code means for causing acomputer to perform the steps of the method in accordance with thepresent disclosure when said computer program is carried out on thatcomputer.

As used herein, the term “computer” may stand for a large variety ofprocessing devices. In other words, also mobile devices having aconsiderable computing capacity can be referred to as computing device,even though they provide less processing power resources than standard“computers”. Needless to say, such a “computer” can be a part of amedical device and/or system. Furthermore, the term “computer” may alsorefer to a distributed computing device which may involve or make use ofcomputing capacity provided in a cloud environment.

The term “computer” may also relate to medical technology devices,fitness equipment devices, and monitoring devices in general, that arecapable of processing data. Preferred embodiments of the disclosure aredefined in the dependent claims. It should be understood that theclaimed method and the claimed computer program can have similarpreferred embodiments as the claimed device and as defined in thedependent device claims.

Preferred embodiments of the invention are defined in the dependentclaims. It shall be understood that the claimed method has similarand/or identical preferred embodiments as the claimed device and asdefined in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the invention will be apparent from andelucidated with reference to the embodiments described hereinafter. Inthe following drawings FIG. 1 shows a simplified schematic illustrationof a monitoring system according to an embodiment of the presentdisclosure;

FIG. 2 shows a simplified schematic illustration of another monitoringsystem according to an embodiment of the present disclosure;

FIG. 3 shows a simplified schematic illustration of a layout of a motionsensor unit in accordance with an embodiment of the present disclosure;

FIG. 4 shows a simplified illustration of an exemplary CTG plotinvolving fetal information, maternal information, and fetal movementinformation;

FIG. 5 shows an exemplary fetal movement trace;

FIG. 6 shows an exemplary embodiment of an augmented fetal movementplot;

FIG. 7 shows another exemplary embodiment of an augmented fetal movementtrace;

FIG. 8 shows another exemplary embodiment of an augmented fetal movementtrace;

FIG. 9 shows another exemplary embodiment of an augmented fetal movementtrace; and

FIG. 10 shows an illustrative block diagram representing several stepsof an embodiment of a method in accordance with the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

In the following, several embodiments of systems and method that canmake use of at least some aspects of the present disclosure will bepresented and elucidated in more detail.

By way of example, FIG. 1 shows a pregnancy monitoring system 10 formonitoring a fetus 18 in a womb or uterus 16 of a to-be-monitoredsubject 12, particularly a pregnant female. Generally, the system 10 maybe applied to an abdominal portion 14 of the subject 12. The system 10may be capable of monitoring fetal medical condition information, suchas fetal motion or, more precisely, fetal heart rate indicative signals.The system may be further capable of monitoring the subject 12, therebyobtaining maternal medical condition information, such as, for instance,uterine contractions.

The system 10 comprises a fetal monitoring transducer 20. The fetalmonitoring transducer 20 may be regarded as a fetal heart ratetransducer, for instance. Commonly, the fetal monitoring transducer 20comprises at least one ultrasound sensor 22 that is capable ofnon-invasively detection fetal movements.

In some applications, the fetal monitoring transducer 20 may be manuallyguided and moved along the abdominal portion 14 of the subject 12 by anoperator in order to find a strong fetal signal. It goes without sayingthat also any displacement of the fetal monitoring transducer 20 at theabdomen may be somehow reflected by a signal provided by the ultrasoundsensor 22. Consequently, a desired fetal signal may be stronglydistorted.

The fetal monitoring transducer 20 may further comprise a housing 24 towhich a contact face or pad 26 may be attached. The pad 26 may beconfigured for contacting the abdominal skin of the subject 12 duringoperation. The ultrasound sensor 22 may be embedded in the housing 24.Further, at least one first motion sensor unit 30 may be associated withthe fetal monitoring transducer 20. Particularly, the at least one firstmotion sensor unit 30 may be provided in the housing 24 as well.Consequently, the ultrasound sensor 22 and the at least one first motionsensor unit 30 may experience basically similar motion occurrences.

The system 10 may further comprise at least one second motion sensorunit 32. The at least one second motion sensor unit 32 may serve as areference motion sensor unit 32 for the first motion sensor unit 30. Thefirst motion sensor unit 30, the second motion sensor unit 32 and, ifalso provided, any further motion sensor unit may be connected to acontrol device 48 via respective signal connectors 34, 36 e.g. viawire-based or wireless signal lines.

The control device 48 comprises a motion assessment unit 50 and a signaloutput unit 52. The control device 48 as such is operable to computefetal movement indicative information. The motion assessment unit 50 isarranged to compute fetal movement grading information, in addition tothe fetal movement indicative information. The output unit 52 may beoperatively coupled with a display and/or a chart printer, e.g. athermal printer that provides a CTG plot. The information provided bythe display or the printer is exemplarily shown in FIG. 4 further below.

The control device 48 may further comprise a motion evaluation unit 56comprising at least one motion verification transducer, wherein themotion assessment unit processes the fetal movement grading informationbased on a motion verification signal provided by the motion evaluationunit. As used herein, the motion verification transducer may be embodiedby one of the motion sensor units 30, 32.

The motion evaluation unit 56 is exemplarily shown in FIG. 1 and FIG. 2as forming part of the control device 48. The motion evaluation unit 56comprises and/or is arranged to be coupled with at least one motionverification transducer. By way of example, the at least one motionverification transducer may be implemented by the at least one motionsensor unit 30, 32. In the alternative, the at least one motionverification transducer may utilize sensor data provided by the at leastone motion sensor unit 30, 32.

The motion evaluation unit 56 is operatively coupled or interrelatedwith the motion assessment unit 50. The motion assessment unit 50processes the fetal movement grading information based on a motionverification signal provided by the motion evaluation unit 56. However,there may be alternative embodiments, wherein the motion evaluation unit56 is separate from but operatively coupled with the control device 48.

The motion evaluation unit 56 may be arranged to determine a level ofrelative motion between the motion sensor units 30 and 32. Based on thisinformation, a motion verification signal may be provided. Based on themotion verification signal, the fetal movement grading information maybe processed.

In some embodiments, the at least one second motion sensor unit 32 maybe associated with a maternal monitoring transducer 40 that is capableof detecting maternal medical condition information. For instance, thematernal monitoring transducer 40 may comprise at least onetocodynamometer transducer 42 that is capable of detecting uterinecontractions. Generally, the maternal monitoring transducer 40 may beconnected to a respective attachment element 44, such as, for instance,a strap that may be attached to the abdominal region 14 of the subject12. It may be preferred that the at least one second motion sensor unit32 is associated with the maternal monitoring transducer 40. By way ofexample, the at least one second motion sensor unit 32 and the maternalmonitoring transducer 40 may be integrated into a common housing (notshown in FIG. 1). It is generally preferred that also the maternalmonitoring transducer 40, particularly the tocodynamometer transducer 42thereof and the at least one second motion sensor unit 32 are arrangedclose to each other and preferably mechanically linked to each other,such that they experience basically similar motion occurrences.

FIG. 2 shows an alternative layout of a pregnancy monitoring system 10a. As can be seen in FIG. 2, a fetal monitoring transducer 20 a may beprovided that may basically correspond to the fetal monitoringtransducer 20 illustrated in connection with FIG. 1. The fetalmonitoring transducer 20 a comprises a first motion sensor unit that iscomposed of two or more components 30 a, 30 b, e.g. distinct sensors,that are spaced apart from each other. By way of example, the motionsensor unit component 30 a may be integrated into the housing 24 whilethe motion sensor unit component 30 b may be attached to an attachmentelement or strap 54.

As can be further seen from the at least one second motion sensor unit32 a, 32 b does not necessarily have to be mechanically linked tomaternal monitoring transducer 40 a and the tocodynamometer transducer42, respectively. As already indicated above, also the second motionsensor unit may be composed of two or more components 32 a, 32 b. Insome embodiments, the tocodynamometer transducer 42 and the components32 a, 32 b of the second motion sensor unit may be coupled to respectiveattachment elements 58, 60, 62. The attachment elements 58, 60, 62generally may be embodied by straps, adhesive strips, patches, suctioncaps, for instance. As can be also seen in FIG. 2, indicated by areference number 64 designating a wireless communication module, medicalcondition information and motion information may be transferredwirelessly.

FIG. 3 shows a simplified layout of a motion sensor unit 30, 32 that maygenerally serve as a motion sensor unit that can be associated with thefetal monitoring transducer 20 and/or the maternal monitoring transducer40. The motion sensor unit 30, 32 may be composed of at least one motionsensor 70, 72. Each of the at least one motion sensor 70, 72 may beconfigured as accelerometer-based motion sensor, for instance. Themotion sensor unit 30, 32 may further comprise a controller unit 74 thatmay be provided with a controller 76 and an input/output port 78. Atleast some or each of the components 70, 72, 74 may be arranged on acarrier strap 80, or in a respective housing or in another suitable way.It shall be understood that those skilled in the art may readilyidentify, deduce and implement similar motion sensor units 30, 32 thatmay be coupled to the monitoring systems 10, 10 a so as to furtherimprove monitoring accuracy and reliability.

It is again emphasized that in at least some embodiments, the motionassessment unit 50 does not necessarily require (external) movementinformation provided by separate motion sensor units 30, 32 as shown inFIG. 1 and FIG. 2. In the alternative, or in addition, the motionassessment unit 50 may be primarily provided with information detectedby the fetal monitoring transducer 20 which may be arranged as an UStransducer, for instance. In further exemplary embodiments, the motionassessment unit 50 is operable to process information provided by thefetal monitoring transducer 20 and information provided by theadditional motion sensor units 30, 32 that detect external movements.

Reference is made to FIG. 4 illustrating an exemplary CTG plot 100. Theplot 100 comprises signal traces 102, 104, 106 which are simultaneouslyrecorded and presented. A common time base for the traces 102, 104, 106is indicated by a time axis 108.

The trace 102 represents a fetal condition signal, particularly a fetalheart rate signal. The trace 104 represents a maternal condition signal,particularly a uterine activity signal. Further, the trace 106represents fetal movements which are indicative of fetal activity andfetal well-being. The trace 106 involves a block representation.Consequently, the presented information is generally referred to asfetal movement blocks. The trace 106 represents a binary signal that isarranged to assume two states, namely a first state where no fetalmovements are present, and a second state where fetal movements arepresent. As already discussed above, the trace 106 may involve wrongindications, e.g. due to external movements and/or signal distortion.

FIG. 5 illustrates a schematic simplified representation of a fetalmovement trace or plot 120 in accordance with the binary trace 106 ofthe CTG plot 100 of FIG. 4. The plot 120 is composed of blocks 122indicating the presence of fetal movements.

In accordance with the present disclosure, it is proposed to augment orenrich the plot 120. Hence, a modified of augmented CTG plot can beprovided.

For instance, a modified augmented signal 130 is shown in FIG. 6. Still,the signal 130 is composed of blocks 132, 134. However, the blocks 132,134, while still having the same height, are visually distinguishableand may have a different pattern, color, and such like.

For instance, the pattern of block 132 indicates the presence of fetalmovements at a sufficiently high reliability level. By contrast, theblock 134 may indicate potential movements which may be howeverattributable to non-fetal movement, e.g. maternal movements, transducermovements/dislocations, etc.

Hence, in accordance with the computed actual level of the fetalmovement grading information, it can be assessed whether the reliabilitylevel is sufficiently high. If this is the case, the genuine movementsignal 132 may be provided. In case where the level of reliability isnot sufficiently high, but where nevertheless movement indications arepresent, the signal 134 involving distinct blocks may clearly indicatethe reduced reliability condition.

The medical staff which is used to binary signals as shown in FIG. 5does not face major challenges in grasping, understanding and finallyaccepting the augmented signal representation.

Similarly, also FIG. 7 illustrates an augmented fetal movement signal140 where the shape, particularly the height or magnitude of involvesblocks 142, 144 is different. The signal 140 is a ternary signal thatcan assume three states.

A first state indicates that no movements at all are present which mayinvolve movements that do not exceed a defined negligibility threshold.A second state is indicated by the pattern of block 142 and indicatesthat fetal movements are present at a defined first accuracy level. Athird state is indicated by the pattern of block 144 and indicates thatfetal movements are present at a defined second accuracy level.

FIG. 8 illustrates a similar augmented fetal movement signal 150 whichhowever comprises a first binary signal plot involving blocks 152 and asecond (top) binary signal plot involving blocks 154. As the signal ofthe second plot may not be enabled when the signal of the first (bottom)plot is not enabled, a three-state or tertiary presentation is provided.The first plot basically corresponds to the plot of FIG. 5. The secondplot provides supplemental fetal movement grading information.

Further reference is made to FIG. 9 illustrating an augmented fetalmovement signal 160 which comprises a first binary signal plot involvingblocks 162. Further, symbols 164 are present which are shown in FIG. 9in an upper plot as capital letters, for illustrative purposes. Rather,icons and graphic symbols may be used so as to improve thecomprehensibility of the augmented signals.

The symbols 164 may provide multi-level or multi-stage informationincluding a type of movement distortion, involving at least one ofmaternal activity, transducer shifting, delayed inertia fetal movement,and characteristic small scale fetal activities. An example for asmall-scale fetal activity is fetal thumb-sucking or fist-sucking.

Hence, the symbols indicate a reduced reliability level of the firstbinary signal plot but also provide further information as to potentialsources of the signal distortions.

In some embodiments, the symbols 164 also may be used in cases where theaccuracy level is sufficiently high, as genuine (non-distorted) fetalmovements have been detected. In these cases, the symbols 164 may forinstance indicate the type of fetal movement, e.g. leg movement, kicks,rolling, arm movement, torso movements, head movements, etc.

As already indicated above, the type of movement may be reflected in thereceived US signal. Hence, characteristic patterns indicate a certaintype of movement. An augmented fetal movement signal based on the fetalmovement indicative information and the fetal movement gradinginformation is provided, wherein a characteristic property of theoriginal fetal movement information is still present in the augmentedfetal movement signal.

A further benefit of the simultaneous presentation of fetal movementindications and the fetal movement grading information is that afrequency of occurrences of unstable measurement conditions, if any, canbe detected. This provides the medical staff with additional informationon the activity of the mother, which for instance may support furtherclinical decisions or actions (e.g. prompting the mother to assume amore resting position in case better CTG quality is desired).

Further reference is made to FIG. 10 schematically illustrating anexemplary embodiment of a method for enhanced pregnancy monitoring inaccordance with the present disclosure.

A step S10 relates to the provision of a fetal monitoring transducerthat is arranged to detect fetal medical condition information,particularly a fetal heart rate signal. Further, the fetal monitoringtransducer may detect fetal movement indicative information. The fetalmonitoring transducer may be arranged as an US Doppler transducer.

An optional step S12 relates to the provision of a maternal monitoringtransducer that is arranged to detect maternal medical conditioninformation, particularly uterine activity indicative information. Thematernal monitoring transducer may be arranged as a tocodynamometertransducer.

A further optional step S14 relates to the provision of addition(external) motion sensor units which may be associated with the fetalmonitoring transducer and/or the maternal monitoring transducer.Further, also distinct motion sensor units may be provided which can beattached to an abdominal portion of an expectant mother.

A further step S16 relates to an initiation of a pregnancy monitoringsession, particularly a CTG examination. The pregnancy monitoringexamination involves at least monitoring a fetal condition signal andfetal movement indicative information.

The examination involves a step S18 which includes an augmented motionassessment which may involve a reliability assessment. Motion assessmentinvolves processing fetal movement grading information.

Further, an output step S20 is provided which typically involves asimultaneous output of a fetal condition signal, particularly a fetalheart rate signal (step S22), a maternal condition signal, particularlya uterine activity indicative signal (step S24), and an augmented fetalmovement signal based on the fetal movement indicative information andthe fetal movement grading information (step S26).

While the invention has been illustrated and described in detail in thedrawings and foregoing description, such illustration and descriptionare to be considered illustrative or exemplary and not restrictive; theinvention is not limited to the disclosed embodiments. Other variationsto the disclosed embodiments can be understood and effected by thoseskilled in the art in practicing the claimed invention, from a study ofthe drawings, the disclosure, and the appended claims.

In the claims, the word “comprising” does not exclude other elements orsteps, and the indefinite article “a” or “an” does not exclude aplurality. A single element or other unit may fulfill the functions ofseveral items recited in the claims. The mere fact that certain measuresare recited in mutually different dependent claims does not indicatethat a combination of these measures cannot be used to advantage.

A computer program may be stored/distributed on a suitable medium, suchas an optical storage medium or a solid-state medium supplied togetherwith or as part of other hardware, but may also be distributed in otherforms, such as via the Internet or other wired or wirelesstelecommunication systems.

Any reference signs in the claims should not be construed as limitingthe scope.

1.-11. (canceled)
 12. A cardiotocographic pregnancy monitoring methodcomprising the steps of: providing a fetal monitoring transducer anddetecting fetal medical condition information involving detecting fetalmovement indicative information, based on ultrasound monitoring;providing a maternal monitoring transducer and detecting maternalmedical condition information, based on tocodynamometer monitoring; andcontrolling a monitoring process involving motion assessment and outputsignal generation; wherein the motion assessment involves processingfetal movement grading information indicative of a movement qualitystate, in addition to the fetal movement indicative information, basedon a motion verification signal, wherein the fetal movement gradinginformation includes a plurality of reliability levels of the fetalmovement indicative information, wherein a first reliability level ofthe plurality of reliability levels corresponds to a distorted fetalmovement identified in the fetal movement indicative information, and asecond reliability level of the plurality of reliability levelscorresponds to an undistorted fetal movement identified in the fetalmovement indicative information, wherein the output signal generationinvolves simultaneously providing: a fetal condition signal, a maternalcondition signal, and an augmented fetal movement signal based on thefetal movement indicative information and the fetal movement gradinginformation, wherein a characteristic property of the original fetalmovement indicative information is still present in the augmented fetalmovement signal, wherein the augmented fetal movement signal representsthe plurality of reliability levels of the fetal movement indicativeinformation to simultaneously display the plurality of reliabilitylevels in relation to the characteristic property of the fetal movementindicative information.
 13. The method as claimed in claim 12, whereinthe motion verification signal is indicative of an actual level ofrelative motion between a first motion verification transducer and asecond motion verification transducer of the motion evaluation unit. 14.The method as claimed in claim 12, wherein the augmented fetal movementsignal involves a base portion including a binary signal indication thepresence of fetal movement solely based on the fetal movement indicativeinformation detected by the fetal monitoring transducer, and anaugmentation portion indicating a signal quality level of the baseportion.
 15. (canceled)
 16. The method as claimed in claim 12, whereinthe fetal condition signal is a fetal heart rate signal.
 17. The methodas claimed in claim 12, wherein the maternal condition signal is auterine activity signal.
 18. A non-transitory computer-readable mediumthat stores therein a computer program product, which, when executed ona processor, causes the processor to: detect a fetal medical conditioninformation involving detecting fetal movement indicative information,based on ultrasound monitoring; detect maternal medical conditioninformation, based on tocodynamometer monitoring; and control amonitoring process involving motion assessment and output signalgeneration; wherein the motion assessment involves processing fetalmovement grading information indicative of a movement quality state, inaddition to the fetal movement indicative information, based on a motionverification signal, wherein the fetal movement grading informationincludes a plurality of reliability levels of the fetal movementindicative information, wherein a first reliability level of theplurality of reliability levels corresponds to a distorted fetalmovement identified in the fetal movement indicative information and asecond reliability level of the plurality of reliability levelscorresponds to an undistorted fetal movement identified in the fetalmovement indicative information, wherein the output signal generationinvolves simultaneously providing: a fetal condition signal a maternalcondition signal, and an augmented fetal movement signal based on thefetal movement indicative information and the fetal movement gradinginformation, wherein a characteristic property of the original fetalmovement indicative information is still present in the augmented fetalmovement signal, wherein the augmented fetal movement signal representsthe plurality of reliability levels of the fetal movement indicativeinformation to simultaneously display the plurality of reliabilitylevels in relation to the characteristic property of the fetal movementindicative information.
 19. The non-transitory computer-readable mediumas claimed in claim 18, wherein the fetal condition signal is a fetalheart rate signal.
 20. The non-transitory computer-readable medium asclaimed in claim 18, wherein the maternal condition signal is a uterineactivity signal.